1. Field
Provided is a fusion polypeptide capable of binding simultaneously to angiopoietin 2, VEGF-C and VEGF-D, preparation and use thereof. Further, provided is a fusion polypeptide capable of binding simultaneously to VEGF-C and VEGF-D, preparation and use thereof.
2. Description of the Related Art
In a higher organism, blood vessels and lymphatic ducts are formed by vasculogenesis and angiogenesis. Vasculogenesis is a process of forming new blood vessels from hemopoietic precursor cells, which mainly occurs only in very limited situations such as development of embryo and fetus, uterine aging, proliferation of placenta, luteinization and wound healing. To the contrary, angiogenesis is a process of forming new blood vessels through proliferation, migration and differentiation of vascular endothelial cells, and excessive angiogenesis becomes a cause of diseases such as cancers, inflammatory diseases (psoriasis, arthritis, and the like), ophthalmic diseases (diabetic retinopathy), lymphatic proliferative diseases (atherosclerosis, and the like), lymphatic metastasis, and neurodegenerative diseases.
Thus, fundamental treatment of excessive angiogenesis-related diseases may be inhibition of angiogenesis, but currently used angiogenesis inhibitors are generally prepared by an organic synthesis method, cause serious side-effects and the effects are not satisfactory. Particularly, an angiogenesis inhibitor that targets blood vessels supplying nutrients to tumor while not directly acting on cancer cells is considered as one of most promising anticancer therapies because it may avoid drug resistance of cancer cells.
VEGF (Vascular endothelial growth factor) is a representative vascular endothelial growth factor controlling formation and development of blood vessels, and interacts with hematoblast, vascular endothelial precursor cells, and mature endothelial cells. In mammals, VEGF-A, B, C, D and P1GF are known as VEGF. The biological function of VEGF is mediated through VEGF receptors VEGFR1, VEGFR2 and VEGFR3. VEGFR has an extracellular domain consisting of 7 immunoglobulin (Ig)-like domains; a transmembrane domain; and an intracellular domain (a regulatory juxtamembrane domain, an intracellular tyrosine kinase domain, several tyrosine residues). VEGF binds to each specific receptor which is then activated. For example, VEGF-A binds to VEGFR1 and VEGFR2 to perform critical functions for growth, migration and survival of vascular endothelial cells, which are essential for vasculogenesis and angiogenesis. VEGF-B and P1GF bind exclusively to VEGFR1, and studies on the function of VEGF-B in angiogenesis and blood vascular system generation are being continued. To the contrary, VEGF-C and -D bind VEGFR2 and VEGFR3 which is then activated, thereby performing critical functions for growth, migration and survival of lymphatic endothelial cells and formation and maintenance of lymphatic ducts.
Angiogenesis by VEGF plays important roles in growth, invasion and metastasis of cancers. It was found that VEGF is overexpressed in various tumors such as lung cancer, stomach cancer, renal cancer, bladder cancer, ovarian cancer and uterine cancer, and it was reported that cancer with highly expressed VEGF has a bad prognosis. Thus, studies on inhibition of growth or metastasis of tumors by inhibiting the activity of VEGF or inhibiting the function of cell receptor VEGFR1 or VEGFR2 are being actively progressed. A representative study employs the VEGF trap, which is a water soluble decoy VEGF receptor manufactured by combining domains of VEGFR1 and VEGFR2 on the surface of cells and has high affinity to VEGF-A. Up to date, the antitumor effect of VEGF has been verified, and it has been reported that the VEGF trap has superior antitumor effect compared to VEGF monoclonal antibody bevacizumab or VEGFR2 antibody DC101.
Meanwhile, Angiopoietin-2 (Ang2) is known as a factor relating to cancer angiogenesis and metastasis, as well as ocular diseases involving abnormal vasculogenesis and rheumatoid arthritis. The biological function of angiopoietin-2 is activated by binding to receptor tyrosine kinase (RTK) Tie2. Tie2 has an extracellular domain consisting of Ig-like domain 1, Ig-like domain 2, 3 EGF-like domains, Ig-like domain 3, and 3 fibronectin type-III domains; a transmembrane domain; and an intracellular tyrosine kinase domain. Among the extracellular subdomains of Tie2, Ig-like domain 2 is essential for angiopoietin binding, and Ig-like domains 1 and 3 are required for stable binding of angiopoietin.
The present disclosure inventors further progressed the concept of VEGF trap, to develop fusion polypeptide that binds simultaneously to VEGF-C, VEGF-D and/or angiopoietin 2 to inhibit their intracellular signal transduction, thus having potent effect of inhibiting proliferation and metastasis of cancer cells and lymphangiogenesis,